Two balls are thrown simultaneously, A vetically upwards with a speed of `20 ms^(-1)` from the ground, and B vetically downwards from height of 40 m with the same speed and along the same line of motion. At what points do the two balls collide? Take `g= 9.8 ms^(-2)`.

Answer

(i) `25 sqrt(3)/2 m//s^(2)` (ii) `(125sqrt(3)/4)^(1//2) m//s` (iii) `25/2 m//s^(2)`

Explanation

`r=2.5 m, a_("net")=25 m//s^(2)`
(a) Radial acceleration `=25 cos theta=25xxsqrt(3)/3 m//s^(2)`
(b) `25 sqrt(3)/2=v^(2)/25rArr v=(125 sqrt(3)/4)^(1//2) m//s`
(c) Tangential acceleration `=25 sin theta=25xx1/2 m//s^(2)`